A new quad-phase (conductivity) and in-phase (susceptibility) conductivity meter was used to evaluate soil salinity that is exacerbating infiltration problems on a large corporate almond/pistachio farm. Initial measurements indicate the use of such a meter may be of value in evaluating some soil constituents for precision management on an extremely large farm in the Central Valley of California.

We are also comparing this instrument to a new dual-band microwave sensor of our own design.

Many techniques are used to measure sorbed soil moisture by microwave attenuation and dielectric techniques. However, all use sophisticated and costly measurement instrumentation and have been limited to moisture measurements of bulk flows (such as in cement plants) where large volumes flow by the immobile microwave detection device.

The testing of a relatively inexpensive microwave source and detector (Gunn-effect diodes in a resonant cavity, separated by an adsorptive matrix) is underway to produce a small, portable, "in-situ" instrument that can be used at varied depths, such as in agronomic in-field soil moisture studies.

Remote Sensing with UAV (Unmanned Aerial Vehicles)

The CropCam is a UAV that flies unassisted to predefined areas within a field and uses a high resolution camera to take photos of those areas from the air.

CropCam Specifications:

Four-foot long Glider with an 8-foot wingspan

Cruising speed of 35 mph; top speed of 60 mph

Up to 60 minutes of flight time – enough for 640 acres at high resolution

Typical altitude between 300-2000 feet (license needed over 400 feet)

Range of up to 1 mile line of sight

Cost of $9000 ($13,000 with software and plane)

Applications:

Agriculture / Ranching

Forestry / Natural Resources

Real Estate / City Planning

Emergency Services / Insurance

Image 1 (top left) is an aerial image of the Utah State University Blue Creek Experiment Station, taken on July 7, 2008, using the CropCam at 2.5 cm resolution. Image 2 (top center) is a small grain trial at the Utah State University Blue Creek Experiment Station, taken on July 7, 2008, using the CropCam at 2.5 cm resolution. Individual plots can easily be seen in this image.

Bare soil imagery easily shows residue (top right). Several images can be combined into a mosaic to show residue of entire field.